Apparatus, system, and method for dual tread treadmill improvements

ABSTRACT

A dual treadle treadmill. The dual treadle treadmill includes a frame, a first treadle, a second treadle, a clutch axle, and a tensioning mechanism. The first treadle and the second treadle are each pivotally coupled with the frame and each have a moving surface. The clutch axle includes an axle, a first driver, and a second driver. The axle is rotatably connected to the frame. The first driver is coupled to the axle by a first clutch. The first clutch transmits torque between the first driver and the axle in response to the first driver rotating in a first direction relative to the axle. The first treadle is connected to the first driver through a first link such that the first driver is rotated in a first direction in response to the first treadle being pivoted in the first direction. The tensioning mechanism maintains a tension on the first link.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 61/609,921 entitled “Apparatus, System, and Method forProviding Resistance in a Dual Tread Treadmill,” which was filed on Mar.12, 2012, and is hereby incorporated by reference.

BACKGROUND

Dual treadle treadmills provide two moving surfaces that articulaterelative to each other. These dual treadle treadmills provide both atreadmill-like motion and a stair climber-like motion. This combinationof motions provides an exercise that simulates climbing a flight ofstairs and provides similar health benefits to users. Existing dualtreadmills include several drawbacks, such as unnatural motions thatresult from existing mechanisms for operating dual treadle treadmills.

SUMMARY

An embodiment of the invention provides a dual treadle treadmill. Thedual treadle treadmill includes a frame, a first treadle, a secondtreadle, a clutch axle, and a tensioning mechanism. The first treadleand the second treadle are each pivotally coupled with the frame andeach have a moving surface. The clutch axle includes an axle, a firstdriver, and a second driver. The axle is rotatably connected to theframe. The first driver is coupled to the axle by a first clutch. Thefirst clutch transmits torque between the first driver and the axle inresponse to the first driver rotating in a first direction relative tothe axle. The first treadle is connected to the first driver through afirst link such that the first driver is rotated in a first direction inresponse to the first treadle being pivoted in the first direction. Thetensioning mechanism maintains a tension on the first link. Otherembodiments of dual treadle treadmills are also described.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 depicts a perspective view of one embodiment of a dual treadtreadmill.

FIG. 2 depicts a perspective view of one embodiment of the dual treadtreadmill of FIG. 1.

FIG. 3 depicts a side view of one embodiment of the drive link and drivelink tensioner of FIG. 2.

FIG. 4 depicts a side view of one embodiment of the pulley system ofFIG. 2.

FIG. 5 depicts another side view of one embodiment of the pulley systemof FIG. 2.

FIG. 6 depicts a perspective view of one embodiment of the clutch axleof FIG. 2.

FIG. 7 depicts another perspective view of one embodiment of the clutchaxle of FIG. 2.

FIG. 8 depicts a perspective view of one embodiment of a rocker drive.

FIG. 9 is a block diagram depicting one embodiment of a system forproviding resistance in a dual tread treadmill.

FIG. 10 depicts a flowchart diagram showing one embodiment of a methodfor providing resistance in a dual treadle treadmill.

FIG. 11 depicts a perspective view of another embodiment of a rockerdrive.

FIG. 12 depicts a perspective view of another embodiment of a rockerdrive.

FIG. 13 depicts a perspective view of an alternative embodiment of adual tread treadmill.

FIG. 14 depicts a perspective view of one embodiment of the torque tubeof FIG. 13.

FIGS. 15A and 15B depict perspective cutaway views of one embodiment ofthe clocking mechanism of FIG. 13.

FIG. 16 depicts a cutaway perspective view of one embodiment of theposition sensor of FIG. 13.

FIG. 17 depicts a cutaway perspective view of one embodiment of thetransmission of FIG. 13.

FIG. 18 depicts a bottom view of one embodiment of the tension balancerof FIG. 13.

Throughout the description, similar reference numbers may be used toidentify similar elements.

DETAILED DESCRIPTION

In the following description, specific details of various embodimentsare provided. However, some embodiments may be practiced with less thanall of these specific details. In other instances, certain methods,procedures, components, structures, and/or functions are described in nomore detail than to enable the various embodiments of the invention, forthe sake of brevity and clarity.

While many embodiments are described herein, at least some of thedescribed embodiments provide a method for providing resistance in adual tread treadmill.

FIG. 1 depicts a perspective view of one embodiment of a dual treadtreadmill 100. The dual tread treadmill 100 includes two treadles 102A,102B (collectively referred to as “the treadles” 102) and an axle 104.In the illustrated embodiment, some components have been removed forclarity. The dual tread treadmill 100 provides a separate pathway forthe travel of each foot of a user.

In some embodiments, the treadles 102 articulate around the axle 104.The treadles 102 may articulate independently. As the treadles 102articulate around the axle 104, an end of each treadle 102 may move in asubstantially upward direction or a substantially downward direction. Insome embodiments, the treadles 102 are synchronized such that when thefirst treadle 102A is at its highest position, the second treadle 102Bis at its lowest position. Motion of the first treadle 102A may belinked to motion of the second treadle 102B, such that in response to anend of the first treadle 102A moving in a substantially downwarddirection, an end of the second treadle 102B moves in a substantiallyupward direction.

Each of the treadles 102A, 102B, in some embodiments, include a movingsurface on which a user may step. The moving surface of a treadle, insome embodiments, includes a belt that translates along a top surface ofthe treadle. In one embodiment, the articulated treadles 102 provide astair stepping motion for a user, in addition to a treadmill motion.

FIG. 2 depicts a perspective view of one embodiment of the dual treadtreadmill 100 of FIG. 1. The dual tread treadmill 100 includes twotreadles 102, a drive link 202A, a clutch axle 204, a pulley system 206,and a generator 208. In some embodiments, the drive link 202A, clutchaxle 204, pulley system 206, and generator 208 manage a fall rate of thetreadles 102.

The drive link 202A, in one embodiment, is connected to one of thetreadles 102 (e.g. 102A). The drive link 202A may move in response tomovement of the connected treadle 102. In some embodiments, one end ofthe drive link 202A moves in an upward direction as the connectedtreadle 102 moves in an upward direction. The drive link 202A may beheld in tension by an attached drive link tensioner. The drive link 202Aand drive link tensioner are described in relation to FIG. 3 below.

As will be appreciated by one skilled in the art, the dual treadtreadmill 100 may include a first drive link 202A attached to the firsttreadle 102A and a second drive link attached to the second treadle102B. The two drive links may work in concert to manage the fall rate ofthe treadles 102.

In certain embodiments, the drive link 202A engages a driver on theclutch axle 204. Motion of the drive link 202A may cause the driver onthe clutch axle 204 to rotate. In some embodiments, the driver isattached to the clutch axle 204 by a one-way clutch that causes theclutch axle 204 to rotate in one direction as the drive link 202A movesup and down. The driver and the clutch axle 204 are described in greaterdetail below.

The pulley system 206 receives rotational motion from the clutch axle204 and translates the rotational motion to the generator 208. Thepulley system 206 may include pulleys of varying sizes that provide agear ratio. The gear ratio of the pulley system 206 may increase ordecrease the rate of rotation provided by the clutch axle 204. In oneembodiment, the gear ratio of the pulley system 206 causes the rate ofrotation at the output of the pulley system 206 to be increased to arate above the rate of rotation provided by the clutch axle 204. Thepulley system is described in greater detail below in relation to FIG.4.

In some embodiments, the generator 208 receives rotation from the pulleysystem 206 and converts the rotation to electrical energy. The generator208 may also provide a braking torque that resists the rotation from thepulley system 206. This braking torque may be translated through thepulley system 206, the clutch axle, and the drive link 202A to thetreadles 102. The translated braking torque may be used by the dualtread treadmill 100 to manage a fall rate of the treadles 102.

The generator 208 may be any type of generator known in the art. Forexample, the generator 208 may be an alternator, a dynamo, a singly-fedgenerator, a doubly-fed generator, or another type of generator.

In some embodiments, the generator 208 may be connected to a variableelectrical load device. The variable electrical load device applies avariable electrical load to the generator 208. Applying an electricalload to the generator 208 may have a braking effect on the generator 208to increase the braking torque provided by the generator 208, thusreducing the fall rate of the treadles 102. The variable electrical loaddevice is described in greater detail below in relation to FIG. 9.

FIG. 3 depicts a side view of one embodiment of the drive link 202A anda drive link tensioner 304 of FIG. 2. The drive link 202A, in oneembodiment, is connected at one end to a treadle 102. Upward anddownward motion of the end of the treadle 102A causes a correspondingupward and downward motion of the attached end of the drive link 202A.

The drive link 202A may be any type of link known in the art. Forexample, the drive link 202A in one embodiment is a roller chain. Inalternative embodiments, the drive link 202A may be a different type ofmotion translation device. For example, the drive link 202A may be acable, a rope, a toothed strap, a toothed belt, or a belt.

In some embodiments, the drive link 202A passes over a clutch driver302. The clutch driver 302 may rotate around the clutch axle 204 inresponse to motion of the drive link 202A.

The drive link 202A may be held in tension by a drive link tensioner304. In one embodiment, the drive link tensioner 304 attaches to asecond end of the drive link 202A and applies tension to the drive link202A. Tension in the drive link may act to keep the drive link engagedwith the clutch driver 302 as the drive link 202A moves.

The drive link tensioner 304 may be any type of tension device known inthe art. For example, the drive link tensioner 304 may be a coil spring.The drive link tensioner may pass over a pulley 306 and be connected toa frame of the dual tread treadmill at an anchor point 308.

FIGS. 4 and 5 depict alternate side views of one embodiment of thepulley system 206 of FIG. 2. The pulley system 206 includes one or morepulleys 402, one or more belts 404, and a flywheel 406. The pulleysystem receives rotational input provided by the clutch axle 204 andprovides rotation to the generator 208 at a rate increased over the rateprovided by the clutch axle 204.

In some embodiments, the flywheel 406 rotates in response to upward anddownward movement of the treadles 102. The flywheel 406 may be locatedat any point in the pulley system 206. In the illustrated embodiment,the flywheel 406 is located at the intersection of the first stage ofthe pulley system 206 and the second stage of the pulley system 206. Insome embodiments, the flywheel 406 acts as a pulley 402 in the pulleysystem 206.

The flywheel 406 may act to store inertia in the pulley system 206 anddampen changes in the rate of fall in the treadles 206. The flywheel 406may be sized to provide desirable dampening characteristics. In oneembodiment the flywheel is an eight and one half pound flywheel.

FIGS. 6 and 7 depict alternative perspective views of one embodiment ofthe clutch axle 204 of FIG. 2. The clutch axle 204 includes a clutchdriver 302, an axle bearing 602, and a clutch 604. The clutch driver 302is similar to the same numbered object described in relation to FIG. 3.The clutch axle 204 translates linear motion from the drive link 202A torotary motion.

The axle bearing 602 supports the clutch axle 204 and allows the clutchaxle 204 to rotate. The axle bearing 602 may be mounted to a frame ofthe dual-tread treadmill 100. The axle bearing 602 may be any type ofbearing known in the art. For example, the axle bearing 602 may be aroller bearing, a ball bearing, or a plain bearing.

In certain embodiments, the clutch axle 204 is supported by a pluralityof axle bearings 602. For example, the clutch axle 204 may be supportedby three axle bearings 602.

The clutch 604, in one embodiment, connects the clutch driver 302 to theclutch axle 204. The clutch 604 passes rotation from the clutch driver302 to the clutch axle 204. The clutch 604 may pass the rotation of theclutch driver 302 to the clutch axle 204 in substantially one direction.For example, the treadmill may include a second drive link 202B similarto the drive link 202A. The clutch 604 may pass rotation from the clutchdriver 302 to the clutch axle 204 when the second treadle 102B and thesecond drive link 202B are moving in an upward direction, butsubstantially not pass rotary motion to the clutch axle 204 (freewheel)when the second drive link 202B and the second treadle 102B are movingin a downward direction. As a result of the above-described action ofthe clutch 604, reciprocating movement of the treadles 102 and the drivelinks 202 will impart rotation of the clutch axle 204 in substantiallyone direction.

In some embodiments, the clutch 604 passes a braking torque from theclutch axle 204 to the to the clutch driver 302. The braking torque maybe created by the generator 208 and passed through the pulley system 206to the clutch axle 204. In some embodiments, the braking torque ispassed by the clutch 604 when the treadle 102B is moving in an upwarddirection.

The clutch 604 may be any type of clutch known in the art. For example,the clutch may be a one-way clutch, a clutch bearing, a one-way needle,a sprag clutch, a ratchet, a freewheel, or a slipper clutch.

In some embodiments, the clutch axle 204 includes a second clutch 702.The second clutch 702, in one embodiment, connects a second clutchdriver 704 to the clutch axle 204. The second clutch 702 passes rotationfrom the second clutch driver 704 to the clutch axle 204. The secondclutch 702 may pass the rotation of the second clutch driver 704 to theclutch axle 204 in substantially one direction. For example, the secondclutch 702 may pass rotation from the second clutch driver 704 to theclutch axle 204 when the treadle 102A and the drive link 202A are movingin an upward direction, but substantially not pass rotary motion to theclutch axle 204 (freewheel) when the drive link 202A and the treadle102A are moving in a downward direction. As a result of theabove-described action of the clutch 604, reciprocating movement of thetreadles 102 and the drive links 202 will impart rotation of the clutchaxle 204 in substantially one direction.

In some embodiments, motions of the first treadle 102A and the secondtreadle 102B are mechanically coordinated. For example, in response to auser stepping on the first treadle 102A and causing an end of the firsttreadle 102A to move downward, a linkage may cause an end of the secondtreadle 102B to move upward. The linkage may also cause the oppositesynchronization such that in response to a user stepping on the secondtreadle 102B and causing the end of the second treadle 102B to movedownward, the linkage may cause the end of the first treadle 102A tomove upward.

In certain embodiments, the drive links 202A, 202B and the clutch axle204 interact such that the clutch axle is driven by a treadle 102 movingin an upward direction. For example, in response to a user stepping onthe first treadle 102A, the end of the first treadle 102A moves in adownward direction, the second treadle 102B moves in an upwarddirection, and the second drive link 202B connected to the secondtreadle may engage the second clutch 702 to pass rotation to the clutchaxle 204. In this manner, a force generated by a user by stepping on atreadle 102 may be converted to rotational motion at the clutch axle204.

In some embodiments, the clutch 604 passes a braking torque from theclutch axle 204 to the to the clutch driver 302. The braking torque maybe created by the generator 208 and passed through the pulley system 206to the clutch axle 204. In some embodiments, the braking torque ispassed by the clutch 604 when the treadle 102B is moving in an upwarddirection.

The clutch 604 may be any type of clutch known in the art. For example,the clutch may be a one-way clutch, a clutch bearing, a one-way needle,a sprag clutch, a ratchet, a freewheel, or a slipper clutch.

The clutch axle 204 may interact with the treadles 102A, 102B, thepulley system 206, and the generator 208 such that the generator isdriven by reciprocal motion of the treadles 102A, 102B.

FIG. 8 depicts a perspective view of one embodiment of a rocker drivedual tread treadmill 800. The rocker drive dual tread treadmill 800includes two treadles 802A, 802B (collectively “treadles” 802), a rocker802 and a rocker axle 806. The treadles 802 are substantially similar tothe treadle 102 described above in relation to FIG. 1. The rocker drivedual tread treadmill 800 translates upward and downward motion of thetreadles 802 to rotary motion which is then controlled by anelectromechanical braking system.

The rocker 804 is connected to the first treadle 802A near a first end808 of the rocker 804 and to the second treadle 802B at a second end 810of the rocker 804. The rocker 804 is connected to a frame of the rockerdrive dual tread treadmill 800 at a position disposed between the firstend 808 of the rocker 804 and the second end 810 of the rocker 804.

In one embodiment, the connection between the rocker 804 and the frameis a rocker axle 806. The rocker axle 806 allows the rocker 804 to pivotabout the rocker axle 806. The rocker axle 806 may include a bearing,such as a roller bearing, a ball bearing, or a plain bearing. In someembodiments, the rocker axle 806 is perpendicular to a treadle axle 812about which the treadles 802 pivot.

In some embodiments, the rocker 804 will rotate back and forth in a “seesaw” motion as the treadles 802 reciprocate upward and downward. Therocker 804 may tie the treadles 802 together such that when one treadle802A moves in a downward direction, the other treadle 802B moves in anupward direction.

The rocker axle 806, in some embodiments, rotates as the treadles 802are moved. Rotation of the rocker axle 806 may be passed through anelectromechanical braking system to restrict the movement of thetreadles 802. For example, the rotation of the rocker axle 806 may bepassed through a series of clutches, chains, and/or pulleys to agenerator, similar to those described above in relation to FIGS. 1-7.Embodiments of rocker drive mechanisms are further discussed below inrelation to FIGS. 11 and 12.

FIG. 9 is a block diagram depicting one embodiment of a system 900 forproviding resistance in a dual tread treadmill 100. The system 900,includes two treadles 102, a two drive links 202, a pulley system 206, agenerator 208, a variable electrical load 902, a rocker 804, an encoder904, and a computer 906. The treadles 102, drive links 202, pulleysystem 206, generator 208, and rocker 804 are substantially similar tothe same-numbered components described above. The system 900 providesresistance to treadle 102 articulation in a dual tread treadmill 100.

As described above, in one embodiment, articulation of the treadles 102causes translation of the drive links 202. Translation of the drivelinks 202 causes rotation of the pulley system 206. Rotation of thepulley system 206 causes rotation of the generator 208 which produceselectrical energy and provides a braking torque back through themechanical system to the treadles 102.

In some embodiments, the generator 208 is electrically connected to avariable electrical load device 902. The variable electrical load device902 provides a variable electrical load to the generator 208, causingthe braking torque produced by the generator 208 to be increased ordecreased. In one embodiment, the variable electrical load device 902 iscontrolled by a computer 906. The computer 906 may direct the variableelectrical load device 902 to increase or decrease an electrical loadapplied to the generator 208 to increase or decrease the fall rate ofthe treadles 102. The computer 906 may give this direction in responseto a user input, in response to a pre-programmed exercise regimen, inresponse to direction from a group exercise leader, in response to oneor more physical characteristics of the user (e.g. heart rate), or anyother trigger.

The variable electrical load device 902 may use any type of variableelectrical load. For example, the variable electrical load device 902may apply a varying resistance to the generator 208 and dissipate theresulting energy as heat. In another example, the variable electricalload device 902 may direct power from the generator 208 to a battery orbatteries at a varying rate. In a further example, the variableelectrical load device 902 may direct power from the generator 208 to anelectrical grid at a varying rate.

In some embodiments, the system 900 includes an encoder 904 thatindicates the position of the treadles 102. The encoder 904 may beelectrically connected to the computer 906 and provide positioninformation to the computer 906.

The encoder 904 may be any type of encoder known in the art. Forexample, the encoder 904 may be an optical encoder connected to therocker 804. In another embodiment, the encoder 904 is a magneticencoder.

The computer 906, in certain embodiments, determines various parametersrelated to operation of the system 900, displays information relating tooperation of the system 900, and controls aspects of the operation ofthe system 900. The computer 906 may receive inputs from an encoder 904,the generator 208, or any other component of the system 900. Thecomputer 906 is described in greater detail in relation to FIG. 10.

FIG. 10 is a block diagram depicting one embodiment of the computer 906of FIG. 9. The computer includes a processor 1002, a memory device 1004,an input/output manager 1006, a display driver 1008, a rate meter 1010.a balance meter 1012, a resistance controller 1014, and a treadleleveler 1016. The computer 906 determines various parameters related tooperation of the system 900, displays information relating to operationof the system 900, and controls aspects of the operation of the system900.

The processor 1002, in one embodiment, is a hardware component thatexecutes instructions of a computer program. The processor 1002 may beany known or future processor capable of executing the functions of thecomputer 906. For example, the processor 1002 may be a microprocessor, acentral processing unit (CPU) a very-large-scale integration (VLSI)integrated circuit (IC), or a digital signal processor (DSP). Theprocessor 1002 may be programmed to perform the functions of thecomputer 906.

In some embodiments, the memory device 1004 stores information for useby the computer 906. The memory device 1004 may be any type of known orfuture computer memory. For example, the memory device 1004 may be orinclude a volatile memory, a non-volatile memory, random access memory(RAM), flash memory, or a read-only memory (ROM). The information storedby the memory device 1004 may include sensor data, program data,calculated data, user input data, or any other data used by the computer906.

The input/output manager 1006, in one embodiment, manages inputs of datato and outputs of data from the computer 906. The input/output manager1006 may include hardware, software, or a combination of hardware andsoftware. Inputs managed by the input/output manager 1006 may includeforce sensor inputs, RPM sensor inputs, user inputs, or other inputs.Outputs managed by the input/output manager 1006 may include raw outputsand calculated outputs.

The display driver 1008, in some embodiments, controls output of thecomputer to a display. The display driver 1008 may manage output to oneor more LCD, LED, or other displays. For example, the display driver1008 may control one or more multi-segment LED displays. In anotherexample, the display driver 1008 may control an output to an LCD screen.

In some embodiments, the rate meter 1010 determines a rate at which thesystem 900 is operated. The rate meter 1010 may receive an input signalthat is related to the rate and compute a rate from the input signal.For example, the input signal may be produced by an optical sensor (notshown). In another example, the input signal may be produced by amagnetic sensor (not shown). In another example, the input signal may beproduced by the generator 208 that produces electrical power as theexercise apparatus is operated. For example, the generator 208 mayproduce alternating current with a waveform that has a period related tothe rate of operation of the system 900. The period may be related tothe rate by gear ratios of the pulley system 206, characteristics of thegenerator 208, the clutch axle 204, and other parameters. The rate meter1010 may calculate a rate, such as a cadence rate for steps on thetreadles 102 using these relationships.

The rate meter 1010 may determine the rate from the input signal bydirecting the processor 1002 to perform an operation on the inputsignal. For example, the processor 1002 may interpret the input signaland apply a calculation based on a gear ratio, sampling rate, or otherparameter of the system 900 to determine the rate. In some embodiments,the rate calculated by the processor 1002 may be an estimate of a rateof action by a user of the exercise apparatus is operated, such ascadence, RPM, or speed (such as miles per hour or kilometers per hour).

The balance meter 1012, in one embodiment, determines the relative usageof the first treadle 102A and the second treadle 102B. For example, auser of the system 900 may favor one leg over the other and regularlyapply more force or step for a longer period of time on the favored leg.As a result, the treadle 102A used by the favored leg may be on averageat a lower position than the treadle 102B used by the non-favored leg.The balance meter 1012 may determine that the average position of thefirst treadle 102A is lower than that for the second treadle 102B anddisplay this information to indicate that one leg is being favored overthe other. The balance meter 1012 may update this informationessentially continuously so that the user can adjust usage to balancehis or her use of the system 900.

In certain embodiments, the balance meter 1012 receives informationabout use of the treadles 102 via an encoder 904. The encoder 904 may beattached to any moving component of the system that reflects relativeusage of the treadles 102. For example, the encoder 904 may be disposedon the rocker 804 and indicate the angle of the rocker 804. In anotherexample, the encoder 904 may be disposed on the treadles 102.

The resistance controller 1014 may act on the variable electrical loaddevice 902. The resistance controller 1014 may direct the variableelectrical load device 902.

FIG. 11 depicts a perspective view of another embodiment of a rockerdrive 1100. The rocker drive 1100 includes a rocker 802, a rocker axle806, a drive gear 1102, a clutch 1104, a clutch shaft 1108, a gear box1112 and a generator 1114. In one embodiment, the rocker 802 and therocker axle 806 are similar to same numbered components described inrelation to FIG. 8. The rocker drive 1100 converts the rocking motion ofthe rocker 802 to electrical energy.

In some embodiments, the various components of the rocker drive system1100 convert the rocking motion of the rocker 802 to rotary motion,which is translated to the generator 1114. The rotary motion may betransformed to increase or decrease the rate of rotary motion. In someembodiments, several components of the rocker drive 1100 are analogousto components of the system described above in relation to FIGS. 2-7.

The drive gear 1102, in one embodiment, rotates in response to rotationof the rocker axle 806. The drive gear 1102 may exhibit a rocking motionas the rocker 802 rocks. In some embodiments, the rocker drive 1100includes two drive gears 1102.

The drive gear 1102 may include a drive link 1103. The drive link 1103may engage the drive gear 1102 and be translated as the drive gear 1102rotates. In one embodiment, the rocker drive 1100 includes two drivegears 1102, each with an attached drive link 1103. The drive links 1103may be wrapped around the drive gears 1102 in opposite directions.

In some embodiments, the clutch 1104 receives rotary motion from thedrive link 1103 and passes the rotary motion to a clutch shaft 1108. Theclutch 1104 may pass rotary motion in only one direction. In someembodiments, the rocker drive 1100 includes two clutches 1104. The twoclutches 1103 may interact with two drive links 1103 configured to eachallow rotation of the clutch shaft 1108 in the same direction. Theresulting output rotation of the clutch shaft 1108 may be rotation in asingle direction as the rocker 802 rocks.

One or more springs 1106 may be operable to control rotation of thedrive gears 1102, the drive links 1103, and/or the clutches 1104. Thesprings 1106 may act to prevent or reduce backlash in the rocker drivesystem 1100.

The gear box 1112, in one embodiment, changes the rate of rotationprovided by the clutch shaft 1108 and provides the changed rotation tothe generator 1114. The gear box 1112 may be any type of known gear box,including a transmission, a pulley system, and the like. The generator1114 may be similar to the generator 208 described above. The generator1114 may be managed and regulated as described above.

FIG. 12 depicts a perspective view of another embodiment of a rockerdrive 1200. The rocker drive 1200 operates as described in FIG. 12 andis similar to the rocker drive 1100 of FIG. 11.

FIG. 13 depicts a perspective view of an alternative embodiment of adual tread treadmill 1300. The dual tread treadmill 1300 includes afirst treadle 1302A, a second treadle 1302B (collectively, “treadles1300”), a frame 1304, a clutch axle 1306, a transmission 1308, agenerator 1310, a rocker 1312, a tensioning mechanism 1314, and a tailroller 1316. In the illustrated embodiment, some components have beenremoved for clarity. The dual tread treadmill 1300 provides a separatepathway for the travel of each foot of a user.

The treadles 1302, in some embodiments, are pivitolly connected to theframe 1304. The treadles 1302 pivot around a treadle axis 1318. Incertain embodiments, the treadle axis 1318 is defined by an axledisposed near a rear end of the treadles 1302. In certain embodiments,the treadle axis 1318 is co-located with the tail roller 1316.

In some embodiments, the tail roller 1316 is rotatably connected to theframe 1304 at a first connection 1320A and a second connection 1320B.The first connection 1320A and the second connection 1320B may be anytype of rotatable connection known in the art. For example, the firstconnection 1320A and the second connection 1320B may be roller bearings,ball bearings, or plain bearings.

The tail roller 1316, in one embodiment, is not supported by the framebetween the first connection 1320A and the second connection 1320B. Inother words, the tail roller 1316 may span the distance between thefirst connection 1320A and the second connection 1320B withoutadditional connections to the frame between the first connection 1320Aand the second connection 1320B.

In some embodiments, the tail roller 1318 is driven by a motor 1322. Themotor 1322 may be operably connected to the tail roller by a drivelinkage, such as a belt, a chain, or a gear train. The motor 1322 may beany type of motor known in the art. Operation of the motor 1322 maycause the tail roller 1316 to rotate.

In some embodiments, the tail roller 1316 interfaces with movingsurfaces on the treadles 1302. Rotation of the tail roller 1316 maycause the moving surfaces to translate along the treadles 1302.

The frame 1304 provides a structure upon which other components of thedual tread treadmill 1300 are connected. The clutch axle 1306, thetransmission 1308, the generator 1310, and the rocker 1312 may performfunctions similar to same named components described above and aredescribed in further detail below.

In one embodiment, the rocker 1312 synchronizes motion of the treadles1302 and rotates around an axis that is parallel to the treadle axis1318. The rocker 1312 is described in greater detail in relation toFIGS. 14-15B below.

FIG. 14 depicts a perspective view of one embodiment of the rocker 1312of FIG. 13. The rocker 1312 rotates around a rocker axis co-located witha rocker axle 1402. The rocker 1312 is connected to the frame 1304 atthe rocker axle 1402. The rocker 1312 synchronizes motion of thetreadles 1302 such that as an end of the first treadle 1302A is at itshighest point, an end of the second treadle 1302B is at its lowestpoint. The rocker 1312 also synchronizes motion of the treadles suchthat as the end of the first treadle 1302A is moving in a firstdirection, the end of the second treadle 1302B is moving in an opposing,second direction.

In some embodiments, the rocker 1312 includes a plurality of arms 1404.The arms 1404 may include one or more forward facing arms 1404A and oneor more rearward facing arms 1404B. The arms 1404 may be in mechanicalcommunication with the treadles 1302.

In one embodiment, the rocker 1312 may include a torque tube 1406. Thetorque tube 1406 may include a substantially hollow tube configured totransmit the forces applied to the rocker 1312 in operation. The torquetube 1406 may be substantially lighter than a solid body capable oftransmitting the same forces.

In one embodiment, the rocker 1312 may include one or more structurescapable of being observed by a sensor to indicate the position of therocker 1312. For example, the rocker 1312 may include one or moreflanges 1408 that interact with an optical sensor. One embodiment of asensor is described in greater detail below in relation to FIG. 16.

FIGS. 15A and 15B depict perspective cutaway views of one embodiment ofthe rocker 1312 of FIG. 13. The rocker 1312 is rotatably connected tothe frame 1304 and synchronizes the motion of the treadles 1302.

In one embodiment, the first treadle 1302A is connected to the rocker1312 by a first drag link 1502A. The first drag link 1502A may rotatablyconnect to the first treadle 1302A at a first connection point. Thefirst connection point may be disposed on a first axle 1504A connectedto the first treadle 1302A. The first axle 1504A may be substantiallyparallel to the treadle axle 1318.

The first drag link 1502A may be rotatably connected to the rocker 1312on one of the arms 1404 of the rocker 1312. For example, the first draglink 1502A may connect to a forward facing arm 1404A of the rocker 1312.As a result, the first drag link 1502A may connect to the rocker 1312 ata position closer to a forward end of the treadmill than the rockeraxis.

The first drag link 1502A translates a pivoting motion of the firsttreadle 1302A to the rocker 1312. As the first treadle 1302A pivots in afirst direction, the first drag link 1502A causes the rocker 1312 topivot in the first direction.

In some embodiments, the second treadle 1302B is connected to the rocker1312 by a second drag link 1502C. The second drag link 1502C mayrotatably connect to the second treadle 1302B at a second connectionpoint. The second connection point may be disposed on a second axle1504B connected to the second treadle 1302B. The second axle 1504B maybe substantially parallel to the treadle axle 1318.

The second drag link 1502C may be rotatably connected to the rocker 1312on one of the arms 1404 of the rocker 1312. For example, the second draglink 1502C may connect to a rearward facing arm 1404B of the rocker1312. As a result, the second drag link 1502C may connect to the rocker1312 at a position closer to a rearward end of the treadmill than therocker axis.

The second drag link 1502C translates a pivoting motion of the secondtreadle 1302B to the rocker 1312. As the second treadle 1302A pivots ina first direction, the second drag link 1502C causes the rocker 1312 topivot in an opposing, second direction.

In some embodiments, the dual treadle treadmill 1300 includes additionaldrag links 1502. The additional drag links 1502 may add rigidity to thetreadles 1302. For example, in one embodiment, the first treadle 1302Ais connected to the rocker 1312 by a first secondary drag link 1502B andthe second treadle 1302B is connected to the rocker 1312 by a secondsecondary drag link 1502D.

The first secondary drag link 1502B and the second secondary drag link1502D are configured and connected similarly to the first drag link1502A and the second drag link 1502C, respectively. The secondary draglinks 1502B, 1502D may be separated from their corresponding primarydrag links 1502A, 1502C by a distance. For example, the first secondarydrag link 1502B may be rotatably connected to the first treadle 1302A ata point on the first axle 1504A that is disposed a distance from thefirst connection point at which the first drag link 1502A is connected.Similarly, the second secondary drag link 1502D may be rotatablyconnected to the second treadle 1302B at a point on the second axle1504B that is disposed a distance from the second connection point atwhich the second drag link 1502C is connected.

FIG. 16 depicts a cutaway perspective view of one embodiment of aposition sensor 1602 for the dual treadle treadmill 1300 of FIG. 13. Theposition sensor 1602 includes the position sensor 1602 and an encoder1408. The position sensor 1602 senses a position of the treadles 1302.

In one embodiment, the position sensor 1602 is attached to the frame1304. The position sensor 1602 senses a position of the treadles 1302 bysensing an encoder 1408 that changes position as the treadles 1302 move.The sensor 1602 may be any type of sensor known in the art. For example,the sensor 1602 may be an optical sensor or a magnetic sensor.

In some embodiments, the sensor 1602 is an optical sensor and theencoder 1408 includes a flange attached to the rocker 1312. As therocker 1312 rotates, the position of the attached encoder 1408 changes.The sensor 1602 observes if the encoder 1408 is in a particularposition. In response to the encoder 1408 being in a particularposition, the sensor 1602 sends a signal to a computer (not shown) toindicate the position of the encoder 1408. The computer may interpretthis signal to infer a position of the treadles 1302.

FIG. 17 depicts a cutaway perspective view of one embodiment of thetransmission 1308 of FIG. 13. The transmission 1308 includes a pluralityof pulleys 1702A-1702F (collectively “pulleys 1702”), and a plurality ofbelts 1704A-1704C (collectively “belts 1704”). The transmission 1308changes a rate of rotation and transmits torque from the clutch axle1306 to the generator 1310.

The pulleys 1702, in one embodiment, include a first pulley 1702A and asecond pulley 1702B. The first pulley 1702A is coupled to the axle ofthe clutch axle 1306. The first pulley 1702A interfaces with a firstbelt 1704A. The belt 1704A also interfaces with the second pulley 1704Band transfers torque from the first pulley 1702A to the second pulley1702B.

In one embodiment, the first pulley 1702A and the second pulley 1702Bhave different diameters so as to produce a gear ratio. In oneembodiment, the first pulley 1702A has a larger diameter than the secondpulley 1702B, resulting in a higher rate of rotation at the secondpulley 1702B than at the first pulley 1702A.

The first pulley 1702A, in certain embodiments, is rigidly attached tothe axle of the clutch axle 1306 such that the first pulley 1702Arotates with the clutch axle 1306 and transmits torque to and from theclutch axle 1306. In another embodiment, the first pulley 1702A isconnected to the axle of the clutch axle 1306 by a smoothing clutch1706. The smoothing clutch 1706 may decouple the first pulley 1702A fromthe clutch axle 1306 in response to the first pulley 1702A spinning at arate faster than the axle of the clutch axle 1306. Decoupling the firstpulley 1702A (and, subsequently, the remainder of the transmission 1308and the generator 1310) from the clutch axle 1306 (and, subsequently,the treadles 1302), may smooth the motion of the treadles 1302 undercertain circumstances and result in a motion that a user may deem morenatural.

In some embodiments, the transmission 1308 includes a third pulley 1702Cand a fourth pulley 1702D. The third pulley 1702C is coupled to thesecond pulley 1702B. The third pulley 1702C interfaces with a secondbelt 1704B. The second belt 1704B also interfaces with the fourth pulley1704D and transfers torque from the third pulley 1702C to the fourthpulley 1702D.

In one embodiment, the third pulley 1702C and the fourth pulley 1702Dhave different diameters so as to produce a gear ratio. In oneembodiment, the third pulley 1702C has a larger diameter than the fourthpulley 1702D, resulting in a higher rate of rotation at the fourthpulley 1702D than at the third pulley 1702C.

The third pulley 1702C, in certain embodiments, is rigidly attached tothe second pulley 1702B such that the third pulley 1702C rotates withsecond pulley 1702B and transmits torque to and from the second pulley1702B. In another embodiment, the third pulley 1702C is connected to thesecond pulley 1702B by a smoothing clutch (not shown). The smoothingclutch may decouple the third pulley 1702C from the second pulley 1702Bin response to the third pulley 1702C spinning at a rate faster than thesecond pulley 1702B. Decoupling the third pulley 1702 (and,subsequently, the remainder of the transmission 1308 and the generator1310) from the second pulley 1702B (and, subsequently, the treadles1302), may smooth the motion of the treadles 1302 under certaincircumstances and result in a motion that a user may deem more natural.

As will be appreciated by one skilled in the art, the transmission 1308may have any number of belts 1704 and any even number of pulleys 1702.The transmission 1308 may have one or more smoothing clutches 1706. Thetransmission may have a smoothing clutch at any interface betweenpulleys and/or axles. The transmission may produce any desired gearratio to increase or decrease the speed of rotation produced at theclutch axle 1306.

The belts 1704 may be any type of rotation transmission device known inthe art. For example, the belts 1704 may include belts, toothed belts,v-belts, chains, cables, ropes, or the like. The pulleys 1702 mayinclude corresponding structures appropriate to interface with the belts1704, such as teeth or grooves. The transmission may include anycombination of types of belts 1704, such as a first stage poly-v beltand a second stage smooth belt, or belts of differing sizes. In analternative embodiment, the transmission may include a gear train, agearbox, a planetary gear, gears, a hydrostatic transmission, ahydrodynamic transmission, or the like.

FIG. 18 depicts a bottom view of one embodiment of the tensioningmechanism 1308 of FIG. 13. The tensioning mechanism includes a flexiblelinkage 1808 and one or more tensioning pulleys 1810A, 1810B(collectively “1810”). The tensioning mechanism 1308 applies andmaintains tension on links 1802A, 1802B (collectively “1802”) thattransmit motion from the treadles 1302 to the clutch axle 1306.

The links 1802 are connected to the treadles 1302 and interact withdrivers 1804A, 1804B (collectively “1804”) on the clutch axle 1306 torotate the drivers 1804. The links 1802 and drivers 1804 may be similarto the drive links and drivers described above in relation to FIGS. 2-7.In some embodiments, the links 1802 are toothed belts and the drivers1804 include teeth to interface with the teeth on the links 1802.

The links 1802 may be connected to the tensioning mechanism 1308 tomaintain tension in the links 1802. In one embodiment, the first link1802A may be connected to a first end of the flexible linkage 1808. Theflexible linkage 1808 may then be routed around a portion of a firsttensioning pulley 1810A. A second end of the flexible linkage 1808 maybe connected to the second link 1802B. In some embodiments, the firsttensioning pulley 1801A is rotatably attached to the frame 1304. Theposition of the first tensioning pulley 1810A relative to the frame 1304may be adjustable so as to adjust the tension applied to the links 1802.

In some embodiments, the tensioning mechanism 1308 includes a secondtensioning pulley 1810B. The flexible linkage 1808 may be routed aroundboth a portion of the first tensioning pulley 1810A and a portion of thesecond tensioning pulley 1810B. The second tensioning pulley 1810B maybe rotatably attached to the frame 1304 and the position of the secondtensioning pulley 1810B may be adjustable relative to the frame 1304and/or the first tensioning pulley 1810A.

The tension applied to each of the links 1802A, 1802B by the flexiblelinkage 1808 is substantially parallel. In some embodiments, the forceapplied by the flexible linkage 1808 to both the first link 1802A andthe second link 1802B is substantially directed toward a rear end of thedual treadle treadmill 1300.

The flexible linkage 1808 may be any type of flexible linkage known inthe art. For example, the flexible linkage 1808 may be a cable, a rope,a chain, a belt, or the like.

Although the operations of the method(s) herein are shown and describedin a particular order, the order of the operations of each method may bealtered so that certain operations may be performed in an inverse orderor so that certain operations may be performed, at least in part,concurrently with other operations. In another embodiment, instructionsor sub-operations of distinct operations may be implemented in anintermittent and/or alternating manner.

It should also be noted that at least some of the operations for themethods described herein may be implemented using software instructionsstored on a computer useable storage medium for execution by a computer.Embodiments of the invention can take the form of an entirely hardwareembodiment, an entirely software embodiment, or an embodiment containingboth hardware and software elements. In one embodiment, the invention isimplemented in software, which includes but is not limited to firmware,resident software, microcode, etc.

Furthermore, embodiments of the invention can take the form of acomputer program product accessible from a computer-usable orcomputer-readable storage medium providing program code for use by or inconnection with a computer or any instruction execution system. For thepurposes of this description, a computer-usable or computer readablestorage medium can be any apparatus that can store the program for useby or in connection with the instruction execution system, apparatus, ordevice.

The computer-useable or computer-readable storage medium can be anelectronic, magnetic, optical, electromagnetic, infrared, orsemiconductor system (or apparatus or device), or a propagation medium.Examples of a computer-readable storage medium include a semiconductoror solid state memory, magnetic tape, a removable computer diskette, arandom access memory (RAM), a read-only memory (ROM), a rigid magneticdisk, and an optical disk. Current examples of optical disks include acompact disk with read only memory (CD-ROM), a compact disk withread/write (CD-R/W), and a digital video disk (DVD).

An embodiment of a data processing system suitable for storing and/orexecuting program code includes at least one processor coupled directlyor indirectly to memory elements through a system bus such as a data,address, and/or control bus. The memory elements can include localmemory employed during actual execution of the program code, bulkstorage, and cache memories which provide temporary storage of at leastsome program code in order to reduce the number of times code must beretrieved from bulk storage during execution.

Input/output or I/O devices (including but not limited to keyboards,displays, pointing devices, etc.) can be coupled to the system eitherdirectly or through intervening I/O controllers. Additionally, networkadapters also may be coupled to the system to enable the data processingsystem to become coupled to other data processing systems or remoteprinters or storage devices through intervening private or publicnetworks. Modems, cable modems, and Ethernet cards are just a few of thecurrently available types of network adapters.

Although specific embodiments of the invention have been described andillustrated, the invention is not to be limited to the specific forms orarrangements of parts so described and illustrated. The scope of theinvention is to be defined by the claims appended hereto and theirequivalents.

What is claimed is:
 1. A dual treadle treadmill comprising: a frame; afirst treadle having a first moving surface, the first treadle pivotallycoupled with the frame; a second treadle having a second moving surface,the second treadle pivotally coupled with the frame; a clutch axlecomprising: an axle rotatably connected to the frame; a first drivercoupled to the axle by a first clutch, the first clutch to transmittorque between the first driver and the axle in response to the firstdriver rotating in a first direction relative to the axle; wherein thefirst treadle is connected to the first driver through a first link suchthat the first driver is rotated in a first direction in response to thefirst treadle being pivoted in the first direction; a tensioningmechanism to maintain a tension on the first link.
 2. The dual treadletreadmill of claim 1, wherein the first link is selected from the groupconsisting of a chain, a toothed belt, a belt, and a cable.
 3. The dualtreadle treadmill of claim 1, wherein the driver is selected from thegroup consisting of a toothed pulley, a sprocket, and a pulley.
 4. Thedual treadle treadmill of claim 1, wherein: the clutch axle furthercomprises a second driver coupled to the axle by a second clutch, thesecond clutch to transmit torque between the second driver and the axlein response to the second driver rotating in the first directionrelative to the axle; the second treadle is connected to the seconddriver through a second link such that the second driver is rotated inthe first direction in response to the second treadle being pivoted inthe first direction; and the second link is tensioned by the tensioningmechanism.
 5. The dual treadle treadmill of claim 4, wherein thetensioning mechanism comprises: a tensioning pulley rotatably connectedto the frame; a flexible linkage connected to the first link and thesecond link; wherein the flexible linkage is routed around a portion ofthe tensioning pulley such that tension is applied by the flexiblelinkage to the first link and the second link in substantially paralleldirections.
 6. The dual treadle treadmill of claim 5, wherein thetensioning mechanism further comprises: a second tensioning pulleyrotatably connected to the frame; wherein the flexible linkage is routedaround a portion of the tensioning pulley and the second tensioningpulley such that tension is applied by the flexible linkage to the firstlink and the second link in substantially parallel directions.
 7. Thedual treadle treadmill of claim 5, wherein the flexible linkage isselected from the group consisting of a cable, a rope, a chain, and abelt.
 8. A dual treadle treadmill comprising: a frame; a first treadlehaving a first moving surface, the first treadle pivotally coupled withthe frame; a second treadle having a second moving surface, the secondtreadle pivotally coupled with the frame; a clutch axle comprising: anaxle rotatably connected to the frame; a first driver coupled to theaxle by a first clutch, the first clutch to transmit torque between thefirst driver and the axle in response to the first driver being rotatedin a first direction relative to the axle; wherein the first treadle isconnected to the first driver through a first link such that the firstdriver is rotated in a first direction in response to the first treadlebeing pivoted in the first direction; a transmission to transmit torquebetween the axle and a generator.
 9. The dual treadle treadmill of claim8, wherein the transmission comprises one or more smoothing clutches todecouple the axle from the generator in response to a clutch componentmore closely connected to the generator rotating faster than a clutchcomponent more closely connected to the axle.
 10. The dual treadletreadmill of claim 9, wherein the smoothing clutch is of a type selectedfrom the group consisting of a one-way clutch, a clutch bearing, aone-way needle, a sprag clutch, a ratchet, a freewheel, and a slipperclutch.
 11. A dual treadle treadmill comprising: a frame; a firsttreadle having a first moving surface, the first treadle pivotallycoupled with the frame; a second treadle having a second moving surface,the second treadle pivotally coupled with the frame; a generatoroperably associated with the first treadle such that the generator isdriven in response to the first treadle pivoting relative to the frame;a rocker in mechanical communication with the first treadle and thesecond treadle, the rocker to synchronize the first treadle and thesecond treadle such that when the first treadle is at its highestposition, the second treadle is at its lowest position; and a sensor tosense the position of the first treadle relative to the second treadle.12. The dual treadle treadmill of claim 11, wherein the sensor isconnected to the frame and positioned to read an encoder on the rocker.13. The dual treadle treadmill of claim 12, wherein the encodercomprises a flange attached to the rocker, the flange to interact withthe sensor when the rocker is within a range of rotation.
 14. The dualtreadle treadmill of claim 11, wherein the sensor is an optical sensor.15. The dual treadle treadmill of claim 11, further comprising a tailroller disposed at a treadle axis about which the first treadle and thesecond treadle pivot, wherein: the tail roller is driven by a motor tocause the first moving surface and the second moving surface to move;the tail roller is rotatably connected to the frame at a firstconnection near a first end of the tail roller and a second connectionnear a second end of the tail roller; the first moving surface and thesecond moving surface interface with the tail roller between the firstconnection and the second connection.
 16. The dual treadle treadmill ofclaim 15, wherein the tail roller is unsupported by the frame betweenthe first connection and the second connection.